It is common practice amongst small fishing vessel operators to hire crew off the wharf for fishing trips. Those hired have a varied background and may be taken on board without the skipper being fully aware of their seagoing experience or lack thereof. In order to learn safe working skills and practices on small fishing vessels such as the RYANE SISTERS, novice deckhands rely greatly upon experienced crewmen to provide on-the-job training. At the time of the occurrence, there were no regulatory certification or minimum training requirements for deck crew on small fishing vessels. The injured deckhand was on his second trip to sea on a scallop dragger and was learning the job as he performed it. He may not have been fully aware of the shipboard practice not to stand, work, or pass under a suspended load. The scallop box could have been retrieved from under the dump table after it was safely shored-up or placed in the down position. The topping winch power was such that shock loading could have occurred during times when the table contents were being dumped. The raised table may have been tugged against its anchored hinges by a winch pull in excess of the SWL of the cable. This would cause extreme tensile stress and cable damage. The block was not the proper type for use with a 1.27 cm lifting cable under heavy load. The undersized block diameter imposed an excessive bending moment on the cable causing severe deformation, cable crushing, and accelerated wear which greatly reduced its lifespan. Microscopic examination of the broken ends of several strands showed necking and rupture consistent with overstress failure. TSB Engineering Laboratory report LP 90/97 on Cable Failure is available upon request from the TSB.Analysis It is common practice amongst small fishing vessel operators to hire crew off the wharf for fishing trips. Those hired have a varied background and may be taken on board without the skipper being fully aware of their seagoing experience or lack thereof. In order to learn safe working skills and practices on small fishing vessels such as the RYANE SISTERS, novice deckhands rely greatly upon experienced crewmen to provide on-the-job training. At the time of the occurrence, there were no regulatory certification or minimum training requirements for deck crew on small fishing vessels. The injured deckhand was on his second trip to sea on a scallop dragger and was learning the job as he performed it. He may not have been fully aware of the shipboard practice not to stand, work, or pass under a suspended load. The scallop box could have been retrieved from under the dump table after it was safely shored-up or placed in the down position. The topping winch power was such that shock loading could have occurred during times when the table contents were being dumped. The raised table may have been tugged against its anchored hinges by a winch pull in excess of the SWL of the cable. This would cause extreme tensile stress and cable damage. The block was not the proper type for use with a 1.27 cm lifting cable under heavy load. The undersized block diameter imposed an excessive bending moment on the cable causing severe deformation, cable crushing, and accelerated wear which greatly reduced its lifespan. Microscopic examination of the broken ends of several strands showed necking and rupture consistent with overstress failure. TSB Engineering Laboratory report LP 90/97 on Cable Failure is available upon request from the TSB. The lifting cable failed as a result of accelerated wear and overstress tensile rupture. The block had an improperly shaped and undersized sheave groove diameter, imposing an excessive bending moment on the lifting cable, severely reducing its lifespan. The topping winch was capable of exerting tensile shock loads in excess of the SWL of the cable when the dump table was being emptied. The deckhand took an unnecessary risk in passing under the suspended dump table. The deckhand suffered a fractured right femur and left tibia as well as scrapes and bruises as a result of being struck by the falling dump table. The injured deckhand was on his second trip to sea on a scallop dragger and was learning the job as he performed it. Provincial certification and minimum training requirements for deck crew on small fishing vessels were not yet in effect.Findings The lifting cable failed as a result of accelerated wear and overstress tensile rupture. The block had an improperly shaped and undersized sheave groove diameter, imposing an excessive bending moment on the lifting cable, severely reducing its lifespan. The topping winch was capable of exerting tensile shock loads in excess of the SWL of the cable when the dump table was being emptied. The deckhand took an unnecessary risk in passing under the suspended dump table. The deckhand suffered a fractured right femur and left tibia as well as scrapes and bruises as a result of being struck by the falling dump table. The injured deckhand was on his second trip to sea on a scallop dragger and was learning the job as he performed it. Provincial certification and minimum training requirements for deck crew on small fishing vessels were not yet in effect. The deckhand was seriously injured when he was struck by the falling table after the lifting cable parted. Contrary to safe working practices, the deckhand placed himself in a dangerously unsafe position under the suspended dump table. Post occurrence analysis of the parted cable indicated that it failed as a result of overstress tensile rupture. Contributing to the failure of the cable was the use of an improper type of single sheave block whose rough condition, undersized diameter, and inappropriate sheave geometry caused accelerated wear and premature cable damage.Causes and Contributing Factors The deckhand was seriously injured when he was struck by the falling table after the lifting cable parted. Contrary to safe working practices, the deckhand placed himself in a dangerously unsafe position under the suspended dump table. Post occurrence analysis of the parted cable indicated that it failed as a result of overstress tensile rupture. Contributing to the failure of the cable was the use of an improper type of single sheave block whose rough condition, undersized diameter, and inappropriate sheave geometry caused accelerated wear and premature cable damage.